A frightening event in U.S.-Russia relations unfolded in February near Deir al-Zour in eastern Syria, as both sides battled the remnants of the Islamic State. In violation of a 2015 deconfliction agreement that divided the area into zones of Russian and U.S. military control, around 500 pro-Syrian fighters – most of whom spoke Russian, but whose citizenship remains unverified – crossed the Euphrates River to the U.S. side from the Russian-controlled zone. On Feb. 7 these fighters used Russian tanks, artillery, and mortars to attack a U.S.-supported Kurdish opposition outpost located next to a Conoco natural gas plant. Local U.S. forces first fired back at the attackers using anti-tank missiles and machine guns, and then called in massive air strikes as the fighters continued their attack. The resulting four-hour battle killed 200 to 300 of the attacking forces, according to documents released by the Pentagon. The casualties included a large number of fighters from the Wagner mercenary group of Russian and pro-Russian veterans who had earlier fought on Moscow’s side in eastern Ukraine. (No U.S. or Kurdish casualties were reported.)

In other words, at a time of high geopolitical tension, the military forces of one nuclear superpower directly engaged hundreds of heavily armed and hostile citizens of another nuclear superpower, who may or may not have been acting at the behest of that superpower.

Russia’s actions in the wake of this event have been perplexing. The United States used the special deconfliction phone line for Syria with its Russian counterparts “before, during, and after the strike,” according to the Pentagon, presumably making Moscow aware that an American strike was likely. “We were assured by the Russians that there were no Russians involved,” the Pentagon noted. U.S. Defense Secretary Jim Mattis testifiedthat “the Russian high command in Syria assured us it was not their people.” But the Russian foreign ministry later admittedthat five Russian citizens were killed, and still later said that while “Russian service members” did not participate, several dozen Russian (and pro-Russian Ukrainian) citizens were wounded and flown back to Russia for treatment. However, nearly all experts agree that Russia is understating these figures: Unofficial estimates by Russian doctors and family members indicate that at least 80 Russians died, with some reports claiming an even higher toll.

Why did Moscow initially deny any Russians’ involvement, and then downplay the casualty numbers? And why didn’t the Russian Defense Ministry stop the attackers from crossing into the American zone, or warn them about the likelihood of a U.S. counterstrike? Western media have offered two contending explanations: that Wagner acted without the Kremlin’s authorization, or that this was a Kremlin-approved attack that sought to test Washington while maintaining plausible deniability. But neither explanation fully answers all of the puzzles raised by the publicly available evidence, even though both help us understand more generally the opaque relationship between the Russian state and these forces. A different, or perhaps additional, rationale takes into account the ruthless infighting between Russian security forces that goes on regularly, while Russian President Vladimir Putin looks the other way. Russian Defense Ministry motives in Deir al-Zour may actually have centered on domestic politics inside Russia — and been directed against Putin ally and Wagner backer Yevgeny Prigozhin.

The ambiguity of the relationship between Wagner and the Kremlin made U.S. crisis decision-making much more difficult and dangerous — and the situation could well repeat itself. Putin is increasingly turning to Wagner (and other groups like it) in his efforts to expand Moscow’s global reach. Wagner forces, which were used to support pro-Russian rebels in eastern Ukraine, are now believed to be operating under contract to Omar al-Bashir’s government in Sudan. A different Russian private military firm, the RSB group, has claimed to be operating in Libya on behalf of Russian ally Khalifa Haftar, a regional warlord who has often acted outside the command of the U.N.-recognized Libyan government. Thus, some version of the Deir al-Zour events could soon crop up elsewhere, as U.S. and Russian interests around the world remain at odds and the two countries continue to use military means to pursue those interests. Understanding Russia’s relationship with militias like Wagner offers insight not just into the Syrian conflict, but also into other fragile security situations where Russia’s involvement is ambiguous, as well as into the political tensions inside Russia’s national security bureaucracy.

Out of Control

A predecessor group to Wagner called the Slavonic Corps first went into Syria in 2013, primarily to guard energy facilities and free up Syrian forces for fighting. That time around, two commanders were arrested and imprisoned in Russia as illegal mercenaries when they returned home, although the rest of the Slavonic Corps personnel were not prosecuted. In 2016, Wagner, using many of the same fighters as Slavonic Corps, is believed to have given crucial assistance to Syria in recapturing Palmyra from the Islamic State. The Russian online investigative newspaper fontanka.ru provided photographic evidence that Wagner commanders received state medals for their work and had even been welcomed personally at the Kremlin by Putin.

While a March investigative report by the German newspaper Der Spiegel had previously cast doubt on the exact chain of events in Deir al-Zour in February, experts in both the United States and Europe now consider a May New York Timesreport, based on newly released Pentagon documents and interviews, to be the definitive open-source version of the story. This allows Russian military decisions to be analyzed with a higher degree of confidence, and to give each of the contending explanations their due.

The first explanation, suggested by Neil Hauer in Foreign Affairs, is that the Wagner group acted without Moscow’s knowledge or approval. This explanation is also preferred by the Kremlin. Scholars like Deborah Avant who study private military companies term this a “principal/agent problem:” The interests of the principal contracting state may not align with those of the agents it hires to do military tasks, and states cannot sufficiently monitor what agents actually do on the ground.

The Wagner group certainly has distinct interests in Syria, since its service contracts there are ultimately paid by the Syrian state, not Russia, through a complex financial chain. Wagner is believed to be funded by Prigozhin, a prominent Russian military contractor and close Putin ally. Prigozhin is under U.S. sanctions and was recently indictedby the U.S. Attorney General for funding the Internet Research Agency, the St. Petersburg firm responsible for social media interference in the 2016 U.S. presidential election. He owns another opaque St. Petersburg firm called Evro Polis. In late 2016, Evro Polis (with Kremlin approval) reached a memorandum of understanding with the Syrian energy ministry, giving the firm a 25 percent share of oil and gas produced over the next five years in any Syrian fields, processing plants, and infrastructure that the firm helps to “liberate,” protect, and develop. The final contract was signed in January with the support of the Russian Ministry of Energy. Notably, Deir al-Zour is known as Syria’s oil capital. (Prigozhin also has an interest in Sudan’s gold deposits, suggesting that natural resources contracts may play a role in Wagner’s actions elsewhere, too.)

Perhaps, then, Prigozhin and his Wagner colleagues got greedy, trying to seize the area without adequate planning or Russian defense ministry knowledge and support. But leaked U.S. intelligence documents throw this explanation into doubt because they indicate that Prigozhin kept in close contact with Kremlin officials immediately before and after the attack. In late January, Prigozhin even told Syrian authorities that he had permission from an unnamed Russian minister to make a “fast and strong” move that would be a “good surprise” for Syrian President Bashar al-Assad, in the date range where the attack occurred. Furthermore, the Pentagon watched Wagner on the ground for a week before the attack, as the group entered the American zone of control and moved toward the Conoco site. As noted earlier, the United States communicated with the Russian command in Syria throughout. Especially since Wagner trains next doorto the Russian Military Intelligence (GRU) 10th brigade in Krasnodar, it stretches credulity to imagine that Russian military intelligence was not also watching the group, and did not suspect either the Wagner group’s involvement or its target.

Plausible Deniability

Perhaps instead Moscow knew full well what was happening, and intentionally used the Wagner group to test Washington’s willingness to defend its Kurdish allies and maintain a presence in Syria. This explanation has been advanced by the Wall Street Journal and the Institute for the Study of Warfare. Putin himself said publicly in 2012 that private military companies could be “an instrument for the realization of national interests without the direct participation of the government.” In this case, Putin may have thought Washington was so wary of deeper involvement in Syria that Russia could overrun U.S. allies and turn public opinion against the American effort, all while maintaining plausible deniability of the Kremlin’s involvement. This fits a standard claim about Putin: that he follows Vladimir Lenin’s maxim to test opponents with a bayonet, moving forward if he finds mush and stopping if he finds steel. Certainly, a similar logic explains why many state leaders cooperate with armed local power brokers, even when these warlordschallenge their ultimate sovereignty. Such cooperation gives leaders plausible deniability for what are really state-approved actions, allowing them to avoid both condemnation and dangerous conflict escalation with other states.

This explanation implies, not implausibly, that Moscow did not care enough about the lives of the hundreds of loyal Russian veterans serving in the Wagner group to call them back when U.S. intentions became clear. Some claim that even the evacuation of the wounded was delayed, pointing to the fact that a different mercenary unit — not regular Russian forces — had to provide helicopters to remove casualties from the battlefield. Indeed, the Der Spiegel report hints that this is why Moscow was slow to acknowledge the number of casualties involved: It wished to avoid blame for providing inadequate resources to Prigozhin’s men while treating them as cannon fodder.

Competing Networks

The Russian Defense Ministry’s lack of concern about those fighting for Wagner suggests another possibility that has not yet been raised publicly. Perhaps the uniformed Russian military leadership, or some segment of its command, chose not to stop the Wagner group even knowing full well that superior U.S. forces would fight fire with fire. The Defense Ministry may resent Prigozhin’s independence – military forces everywhere have tensions with those not under their command who take actions in their area of operations. High-ranking Russian officers may especially resent Wagner’s special oil and gas contract with the Syrian government.

Indeed, the Russian investigative journalist who has studied Wagner most closely, Denis Korotkov, said in an interview in August 2017 that Russian Defense Ministry financial support for Wagner had “suddenly dried up” earlier that year, as weapons deliveries disappeared and the wages of Wagner personnel plummeted. Something appears to have changed after Palmyra in how the Russian armed forces viewed Wagner’s usefulness.

The Russian state has refused repeated proposals by deputies of the state legislature, the Duma, to legalize the status of private military companies like Wagner, suggesting the Kremlin has mixed feelings at best about these groups’ actions. The military press in Russia has aired many debates about private military companies, too, reinforcing the sense of uncertainty about how the state views them. (Given state control over the media, the opinions expressed in these pieces are probably proxies for some form of bureaucratic infighting.) One of the most interesting sources for this debate has been the weekly newspaper Military-Industrial Courier. Some commentators, like retired General Staff officer Konstantin Sivkov, have seen the private companies as a key component of counter-insurgency warfare — including for the carrying out of “dirty deeds” abroad where the government doesn’t want to reveal its hand — and have urged Russia to legalize them and catch up with the rest of the world. But others have been virulently opposed. Tatiana Gracheva, a General Staff Academy instructor, worries that such groups would compete against the armed forces to hire the best people, and might even launch violence at home to topple the government, under contract to foreign agents.

Prigozhin himself is a civilian with no military background, imprisoned for nine years as a young man for organized crime activities. While any attempt to understand how Russian officers think must remain speculative, the generals might believe that using a convicted criminal to commercialize foreign defense actions distorts Russian national security interests, in a region where they have risked much on behalf of the state. Or, given that concerns about military corruption remain high in Russia, perhaps the generals just wanted a bigger cut of Prigozhin’s oil deal for themselves. For any of these reasons, they might have intentionally failed to share information from the U.S. deconfliction line with the Wagner group in order to send Prigozhin and his forces a message.

There is no publicly available evidence that Russian generals thought or acted this way. But brutal infighting would help explain the extraordinary callousness of Russian military officers to the fate of a large group of Russian veterans — even if the Russian state was simultaneously trying to advance against U.S. interests using plausible deniability. As analysts Brian Taylor and Mark Galeotti have noted, Putin’s Russia has been riven with conflicts between competing informal network groups close to the Kremlin, including many conflicts within the siloviki, the various state ministries responsible for providing security. Putin is believed to use these rivalries (ranging from competition over overlapping responsibilities to fighting over illegal kickbacks and smuggling) to his own benefit, since it keeps the force-wielding agencies of Russia from uniting against him.

Putin is approaching his last constitutionally mandated term as president, and may increasingly be seen as a lame duck. As scholar Henry Halenotes, signs of leadership weakness in patronage-based political systems like Russia’s often lead clients to start searching for new patrons, which can create social instability. If a core group of military commanders resents Prigozhin, maybe it is they who are using their bayonets — under the direction of Russian Defense Minister Sergei Shoygu— not to test Washington, but instead to test a competing circle of other leading figures around Putin.

We may never have enough evidence to solve definitively the puzzles of Russian behavior at Deir al-Zour. But an understanding of Russian politics and security affairs allows us to better interpret the evidence we do have. Since Moscow’s employment of groups like Wagner appears to be a growing trend, U.S. and allied forces should consider the possibility that in various locations around the world, they might end up inadvertently, and dangerously, ensnared in Russia’s internal power struggles.